Today I was doing an impromptu demo of the Squeak system for a friend and
former coworker. As is usually the case with demos, especially ones which
aren't given much forethought, something went wrong.

I thought he might be impressed to see me create a morph, drop it into a
workspace, and then ask it for it's storeString, so I tried that. The image
hanged as though grinding through something of massive computational
expense. I didn't see anything about the polygon morph in question that
would seem to be terribly expensive to serialize as code, and picked it
because it was a relatively simple morph. Fortunately I was quite prepared
for this to go wrong and set the stage accordingly (as the same thing
happened when I tried using storeString to move the welcome screen text into
the 4.0 images that I was making.)

It feels like a performance problem, as though something here was winding up
with a very, very big-O. I tried running the profiler and then reproducing
the problem again, but I need to do cmd-. to get free of the hang, and after
interrupting that way, moving the hand to the top of the screen does not
cause the profiler results to appear, which is a big bummer.

I'm stumped.

When I interrupt the hang, I don't see a totally consistent stack, but I'm
usually in the middle of a #storeOn:, which seems right, and one thing which
struck me as odd was that I will occasionally interrupt and find myself
inside of PasteUpMorph>>storeOn:. Maybe the system is trying to serialize
the owner ivar? It would be funny if I was accidentally trying to store the
whole world, as that seems both wacky and cyclic:)

I'm not sure if it's even a bug, but it seems that I *should* be able to
store morphs.

Oh wow! I just noticed something else that's interesting: experimenting with
this has rapidly obliterated the charge on my battery, too.

Does anyone have any pearls of wisdom that might help me understand better
what's going on here?
-- 
Casey Ransberger
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